Silicone hates me! why won't it CURE!!!!

Hey Mer-peeps!
Okay so, if you've seen my tail making thread you'll know that I'm having some horrid issues with my silicone curing!! :(
So I'm making a list. What is stopping the silicone from curing. If anyone thinks of anything else or whatever - add it on!
Just put the kind of material your using first so we know whats going on :) So if you know something stops latex from curing add it to the list!

Platinum Cure Silicone (addition cure)

- Latex
- Rubber
- Some types of wood
- incorrect ratios. you can have extra part B but never part A
- Whatever you used to clean out your mold with, some soaps leave a residue (Always rinse out thoroughly)
- Release agents; Silicone will only stick to silicone. you do not need a release agent for it. But if you used a release agent to remove the original object from the mold, make sure you wash correctly afterwards
- Mixing containers. They can have residue left in them from their factories, wash them out well!
- Vinyl
- plastic painters drop sheets, use canvas ones instead (or some old sheets)
- vaseline and petroleum based products.
- Gloves; rubber, latex, vinyl (use nitrile gloves if you have to use some)
- the bloody weather (unfortunately there is no way to control this one unless you're in an area where you have air con/climate control
- sulphur based product (Like clay! Go Monster Makers or Go home!)
- Tin Cure or Condensation Cure silicone (I know they're the same thing, but in Australia if you see the words condensation cure you'll now know what you're looking at.)

So that's the start of the list. If anyone has anything to add, go for it. It benefits the community to know what stops different mediums from curing :)
Happy Tailmaking Peoples!

Not to jump too far ahead in your process here but the monfin boots are ALL made out of rubber which will inhibit silicone cure.
Jessica or any others, how do you deal with the proximity to the monofin shoe rubber when doing your final seaming and sealing the fluke faces to the monofin with silicone?

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Originally Posted by Elle

Hey Mer-peeps!
Okay so, if you've seen my tail making thread you'll know that I'm having some horrid issues with my silicone curing!! :(
So I'm making a list. What is stopping the silicone from curing. If anyone thinks of anything else or whatever - add it on!
Just put the kind of material your using first so we know whats going on :) So if you know something stops latex from curing add it to the list!

Platinum Cure Silicone (addition cure)

- Latex
- Rubber
- Some types of wood
- incorrect ratios. you can have extra part B but never part A
- Whatever you used to clean out your mold with, some soaps leave a residue (Always rinse out thoroughly)
- Release agents; Silicone will only stick to silicone. you do not need a release agent for it. But if you used a release agent to remove the original object from the mold, make sure you wash correctly afterwards
- Mixing containers. They can have residue left in them from their factories, wash them out well!
- Vinyl
- plastic painters drop sheets, use canvas ones instead (or some old sheets)
- vaseline and petroleum based products.
- Gloves; rubber, latex, vinyl (use nitrile gloves if you have to use some)
- the bloody weather (unfortunately there is no way to control this one unless you're in an area where you have air con/climate control
- sulphur based product (Like clay! Go Monster Makers or Go home!)
- Tin Cure or Condensation Cure silicone (I know they're the same thing, but in Australia if you see the words condensation cure you'll now know what you're looking at.)

So that's the start of the list. If anyone has anything to add, go for it. It benefits the community to know what stops different mediums from curing :)
Happy Tailmaking Peoples!

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Oh no! I don't want to jinx anything, but so far I have not run into any inhibition issues. I've been using waxed paper from the grocery underneath things. Yogurt cups, styrene cups... since I'm making individual scales I usually lay them out onto little pieces of cardboard once I pull them out of the mold. but of course, now that I've said something, it's all going to go to hell. ;)

Good luck, Elle!

I copied this from a forum I found ageesss ago, so I dont know the source, but here is a list too:

"The addition type (platinum)silicone will not cure at where it contacts the condensation type(tin)
silicone rubber. This is called inhibition or poisoning.
Manufacturers also list the following materials:

- Condensationtype silicone rubber (especially its tin-soap catalyst)
-Unsaturated hydrocarbon solvents
- Sulphur (in vulcanized naturaland synthetic rubbers)
- Phosphor
- Epoxies containing strongamine catalysts
- Isocyanates of urethane resins
- Somepolyester resins
- Tape adhesives
- Metallo-organicsalt-containing compounds (especially tin salts and
heavymetals)
- Plasticizers in plastics (especially vinyl)
-Materials containing nitrogen
- Some modelling clays
- Solderflux
- Wood
- Leather
- Chlorinated products (such asneoprene rubber) "

This list is for all Platinum cure silicone, as far as I'm aware. Again, dont quote me on all this, I didn't write it XD

As for the footpockets, yes the silicone will not cure on them. I had no trouble with my fluke or attaching the body to it, however. As long as there is enough silicone for the fluke/scale layers to attach to, its normally fine :)

I was wondering about the monofin feet too, since they are made of rubber o.O Also, the vaseline thing is confusing. I was under the impression that it inhibited the curing of latex, not silicone. But I am probably wrong as I have not actually made a tail yet.

Does vaseline really mess up curing that badly?
I just pulled my scale sculpt out of their UltraCal30 mould, in which I used Mann's Ease Release on the scales and vaseline around them on the cardboard base. I wiped everything down with water and a bit of dish soap, I hope it doesn't screw up the DragonSkin! Oh no, another thing to be paranoid about.

Finis Competitor monofins have strips of rubber along certain areas of the the fiberglass monofin other than just on the boot. In other words, there is rubber in areas all over the finis competitor, not to mention the foil and merfin which are solid rubber. If you use silicone like mayonaise on a sandwich to seal together the fluke faces and the monofin inside, you will get some degree of silicone inhibition around the rubber strips on the finis competitor.... And I would think the foil and merfin would be a disaster even if you just seal the perimeter and avoid lace for the interior faces. My only thought would be a coating of spray shellac on the exposed rubber faces to serve as a physical barrier.
Any thoughts on rubber in monofin/fluke sealing processes anyone else?

I used petrolium jelly on my extra fins with no curing problem, so I'm not sure! :3

Wait a minute if neoprene rubber also inhibits silicone curing, how the hell do people make those neoprene/silicone hybrid tails? And if vinyl and plastics also inhibit the curing of silicone, what on earth do you put down on the table when you are making molds with clay walls? And urethane and polyester resins? Don't people use those for molds? This thread has taken me to a whole new level of confused, LOL

To be honest, its not a list I wrote so I cant tell you for sure ^^;

This thread hurts my head xD I was previously under the impression that as long as I didn't use latex near it and I used sulphur free clay I would be ok, but this makes my want to run FAR away from silicone and never look back. I guess buying the silicone after making the moulds is out then, since you would need to have the silicone there in the first place before you even start sculpting to test its curing next to basically every single material you are using x.x

I threw out the Vaseline thing in the other thread, but I said there I might be completely wrong :P Seems I probably am according to the others!

I'm not sure about the vaseline thing either. I'm just going on what I've heard...maybe there was a misinterpretation on my end.
Some of the things I listed I think I should've been clearer on such as rubber (particularly because of what monofins are made of) Silicone doesn't bond to rubber. Silicone is stupid like that (curse you silicone!!)
Jessica and I have talked about it on one of the oceanika monofin threads
http://mernetwork.com/index/showthre...in-in-silicone

I'm not saying this is a comprehensive list. These are just things that seem to keep popping up and I thought a ongoing list might be useful. No one has to use it.
There are much more experienced tail makers out there (I really am just a novice) But with the growing number of mers out there trying to make their own tails, every little bit of information helps.

That's why I'm trying as many techniques in my tail as I possibly can, so I can hopefully help someone else in their quest to make their own tail.
If you know something that has been mentioned is wrong send a line out correcting it. Someone was able to use vaseline on their silicone tail with no drama! fantastic, that's one less thing to worry about.
I'm quite happy for this thread to be removed if it is wrong, or inappropriate or unneeded. I just thought a little bit of extra info goes a long way

Personally, I think this thread is really good and should definitely be here. A place for discussion about smaller aspects of tail making can save people trawling through loads of other threads to find the info :=)

:-( I'm disappointed about how sensitive platinum silicone is waaaaah because I wanted to try latex tails first using my epoxy resin mold. Maybe there's hope? I just want someone to tell me it can be done, lol. Lots of cleaning? Surely resin won't absorb latex residue ....
You know that feeling where you just want to make it happen somehow.

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Originally Posted by OceanRose

Personally, I think this thread is really good and should definitely be here. A place for discussion about smaller aspects of tail making can save people trawling through loads of other threads to find the info :=)

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I agree, this is definitely an important and necessary thread!

Quote:

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Originally Posted by OceanRose

:-( I'm disappointed about how sensitive platinum silicone is waaaaah because I wanted to try latex tails first using my epoxy resin mold. Maybe there's hope? I just want someone to tell me it can be done, lol. Lots of cleaning? Surely resin won't absorb latex residue ....
You know that feeling where you just want to make it happen somehow.

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I think if you clean out your mold with warm soapy water once it's set and then clean it with some alcohol to help get the rest of the residue and the alcohol with just dry out.
That's what I hope will become of this thread. All the little tips and tricks from everyone, what makes this harder, what makes this easy, under no circumstances should you ever do this :)
and with mers using all different kinds of mediums! so I know there is a lot of silicone tails out there being made, but it'd be great if someone who does latex or if someone used urethane, even the neoprene tail makers out there as that stuff is a b*tch to hand sew. All that stuff, as it makes it all that much easy for the community.

urethanes are actually fine. smooth on sells brush on urethane as a mold product for use with dragonskin. Fabric coated neoprenes are also find to adhere to silicone. My main issue is to avoid tacky honey like areas around the rubber on monofins.

there is no reason to use vaseline directly in a mold for use with silicone. I use Smooth on's universal release agent if anything.

Quote:

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Originally Posted by OceanRose

:-( I'm disappointed about how sensitive platinum silicone is waaaaah because I wanted to try latex tails first using my epoxy resin mold. Maybe there's hope? I just want someone to tell me it can be done, lol. Lots of cleaning? Surely resin won't absorb latex residue ....
You know that feeling where you just want to make it happen somehow.

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As sensitive and expensive as dragonskin is, I would just make a new mold :) it's just not worth the risk in my opinion...there's no guarantee that you will get rid of all the latex residue :)


when it comes to the issue with rubber monofins, I really recommend reading my first thread :) I used a foil and had a disaster....the thread Elle posted has tons of great info too about rubber monofins and taking precautions with them!

GP,

some urtethanes are fine, but not all....there are different types :) there's urethane caulking that can interfere with silicone and it's likely to cause issues if it's newly cast.



Here's some great info from the tech sheet from dragonskin:

Cure Inhibition – Addition-cure silicone rubber may be inhibited by certain contaminants in or on the pattern to be molded resulting in tackiness at the pattern interface or a total lack of cure throughout the mold. Latex, tin-cure silicone, sulfur clays, certain wood surfaces, newly cast polyester, epoxy or urethane rubber may cause inhibition. If compatibility between the rubber and the surface is a concern, a small-scale test is recommended. Apply a small amount of rubber onto a non-critical area of the pattern. Inhibition has occurred if the rubber is gummy or uncured after the recommended cure time has passed.
Because no two applications are quite the same, a small test application to determine suitability for your project is recommended if performance of this material is in question.



I would like like to add that most plastics are totally fine with silicone :) most vinyl is fine too....I use vinyl gloves with no issue and the tech sheet recommends them as an alternative to latex.

When it comes to vinyl or plastic, I use a somewhat unscientific method....the smell test! If it smells like plastic, keep it away! Plastics and vinyl are usually strong smelling when they're new....over time they off gas and are typically fine to use with silicone. I use the smell test to determine if it's even worth testing the surface. Any newly cast material is more likely to interfere....since your vinal tablecloth is new Elle, I think that's the problem with it!

Plastic food wrap is usually fine to use with silicone :) I have actually poured silicone right on it before.

Surfaces don't really need to be protected too much from silicone....with the exception of carpet! Cured silicone peels right off....but it will bond around the fibers in the carpet!

I know there's more I had to write....I'll have to read all the questions in this thread again later! :) don't be scared away from silicone though! It's so much fun once you get the hang of it! :)

I use waxed paper and plastic coated freezer paper under everything and silicone cures right on top of it! If you make a resin mold, don't use latex then try to use silicone. While the resin doesn't absorb any of the latex, it's not glass smooth and micro-residue will adhere to the surface of the resin mold and you'll ruin your rubber.

To tell you the truth, I don't know why anyone uses latex. It doesn't seem that much cheaper, it smells, you have to do many thin layers, and some people have violent allergies to it. I would love to hear arguments for latex...in a separate thread!

This is a very good idea to be discussing this!

I used vaseline around the edges of my UltraCal mould for my scales, just in case the UltraCal and cardboard stuck together. After the Ultracal was hard, I removed the scales and wiped all the surfaces that had vaseline on it with a wet rag with a bit of dish soap. I was not extremely thorough, but still careful. Last night I poured my first Dragonskin scale sheet and it does not seem to have been affected by the vaseline. Keeping in mind however that very little Dragonskin was applied to the parts of the mould that had been in contact with vaseline.
I'll keep you guys updated if things change!

PearlieMae, you beating up on my Latex!!! :P

Once I used baking parchment on accident instead of waxed paper to cover my work area. (I wasn't thinking, all out of waxed paper, but with LOADS of parchment)

Don't do that, lol.

In case anyone's unfamiliar, baking parchment is silicone infused... Platinum silicone infused (to be food safe, obviously)

So when I tried to "glue" my two pieces of whatever the hell I was making together, I accidentally glued them to the paper. :doh:

If wood is unsafe to use with silicone, what do I place my scales on at the beginning as I start to create my mold? I have a wood board that was for the bottom of a crib that I was hoping to use...

it's some woods. but I'm not sure I understand what it is you're doing. If you're just using the wood for your mold, then I don't see and issue. If your using wood to cast from I'm very interested to see what you are doing

Oh I mean just a surface to place my clay scales on as I prepare my scale sheet for molding

it should be fine. Because you'll be taking the mold off the wooden surface and then pouring the silicone into your mold.

I wouldn't use plywood, though. Who knows what they use to fuse the bits together!

Repeat after me...ALWAYS DO A TEST, FIRST. It's the Pearlie Mae Mantra.

Wow! Thanks for this list! I've been trying to make a fluke mold out of something other than caly, because my sculpting skills suck, and this has been super helpful to know what to avoid!

There's lots of good information in this thread.

I'm using Platsil Gel 10 which is easier to get in the uk compared to DragonSkin, and I get the impression it's not quite so sensitive when it comes to curing inhibition. I haven't ever used Dragon Skin though, so this is just be impression I've gotten.

I tested against Duck Tape (Duck brand) and it cured against both sides of it without any issues. It also cures fine against Vaseline. (I make a few shell/scale moulds using sea shells and silicone putty, and need a releasing agent otherwise the Platsil sticks to the moulds)

The only issue I ever had was when I tested against a flexible polyurethane. I couldn't find a list of ingredients, but it had a strong smell that made me think sulphur... And the silicone directly against it didn't cure.


Sent from my iPhone using Tapatalk

Gel 10 is a faster setting silicone. It's been my understanding that fast setting silicones are less susceptible to cure inhibition in general. I don't think there is much time for other chemicals to cause problems.

I've used gel 10 to do some life casts against a latex bald caps without problems, though I did apply a layer of Vaseline first.
There are fast setting versions of Dragon skin, and Smooth-On sells an accelerant for their silicones. Heat will also accelerate cure time, so perhaps you could minimize cure inhibition issues with speed.

I've found the silicones from both Smooth-On (DragonSkin, Ecoflex, etc) and PolyTek (Gel-10) to be pretty similar. I've used each companies pigments and thickening agents with each other, and even Smooth-On's HyperFolic with Gel-10 and found them to be compatible. I've found that Gel-10 has a higher viscosity but other than that they seem to be the same.

I've never had cure inhibition issues with any of the silicones I've used, but I've followed other people's troubles on various forums, and wood is often the culprit. There are so many glues, vanishes, finishes, paints, etc that could be causing trouble.

I've also seen plaster/stone have problems because they are porous and have absorbed something silicone doesn't like. A number of years ago, a predator costumer had made a stone mold of a predator mask sculpt. He did a couple of latex pulls then tried to run a silicone skin, only to discover that the plaster mold had absorbed the sulphur from the latex and would not allow silicone to cure.

If you're having problems, use a process of elimination to determine the culprit. Is it failing to cure in the bucket? If so, then it's your bucket or the mixing stick or something else at that stage.
Make sure your mixing it thoroughly. If you're having trouble consider getting mixing attachment for a power drill.
If it's on the sculpt then take a sample of each material aside and test a little silicone on it and see what happens. One of those tests will tell you what the problem is.

And don't forget you can call smooth on for help.

The bottom line is don't be intimidated by silicone. In many ways it is easier to work with than latex.

Does anyone have experience with curing silicone on a polyester resin/ fibre-reinforced polymer?

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Originally Posted by Mermaid Alaria

Does anyone have experience with curing silicone on a polyester resin/ fibre-reinforced polymer?

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Do you mean like the kind used in fiberglass molds? My Chewbacca mask mold was a polyster resin fiberglass mold. Never had any issues with platinum cure silicones curing in them including ecoflex, dragonskin, and gel-10.

It's a textured board I want to use for casting part of my tail. It is a type of fiberglass I believe. Good to know. I'm certainly planning to test. :)

I've had a curing issue and I can't figure out why! :( I was doing a touch up on the paint, I used the same pots the same pigment and was careful when mixing it I used a new brush from the same pack I'd used the others from and painted it straight onto the tail. For some reason it hasn't cured at all and its so confusing :( I had basically finished the ta and I need it an a few days time....it's a complete disaster. Is there a way of fixing it?

Quote:

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Originally Posted by KernowMermaid

I've had a curing issue and I can't figure out why! :( I was doing a touch up on the paint, I used the same pots the same pigment and was careful when mixing it I used a new brush from the same pack I'd used the others from and painted it straight onto the tail. For some reason it hasn't cured at all and its so confusing :( I had basically finished the ta and I need it an a few days time....it's a complete disaster. Is there a way of fixing it?

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you will have to clean all the uncured stuff off. try using paint thinner to get off the residue. and good luck!

Wait- I thought you could have extra A but not extra B?
I havent had any curing issues (knock on wood) and I always measure in two cups next to each other, so its close but never exact of course- but I always pour the B into the A so that there is a little more A, since a little B coats the cup it was in...

Is this true that you can have slightly more part A? Or do you not want any more of less of either part? Good idea pouring it into the part A cup of this is true.

Did the vaseline mess it up?